Assembly is a process of joining components, often in an ordered sequence and dictated by a known set of steps. Likewise, disassembly often requires an ordered sequence.
Traditionally, the art of assembly or disassembly depends on a procedure or plan. In the simplest form, the assembly plan may be in the memory of a human assembler. Slightly more complex assemblies may require written instructions. More sophisticated assembly may require a detailed formal protocol, with each step in the assembly mapped out in detail, and using computer programs to control robotic installation.
Whether the assembly is simple, complex or sophisticated, and whether the assembled article is a simple toy, a piece of furniture or an automotive vehicle, for example, it is required that the components and sub-assemblies are in the correct spatial position and have the correct position relative to other components, sub-assemblies and to the assembly itself.